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Son las preguntas y respuestas de SI -NO PREGONEIS ALOS 4 TIEMPOS QUE LAS TENEMOS-
The network address of a class B network node with 132.54.7.3 IP address is: - 132.54.0.0
The standard IEEE 802.3 use information data units called: - Datagrams
Which of the following expressions is a valid MAC address? - 19:B9:05:E6:C4:E5
IPv4 protocol use addresses formed by: - 32 bits
The broadcast address of a class B network node with 132.54.17.13 IP address is: - 132.54.255.255
The protocols of the application layer work over: - TCP or UDP
IPv6 protocol use usually addresses formed by X groups of Y hexadecimal digits, where X and Y are: - 8 and 4 //(no 4 y 8)
We have the address 80.15.12.35:75/web/index.html. 80.15.12.35 represents: - The addres of the network node
Link layer protocols use packets based on: - Datagrams
To connect two different subnetworks at internet layer we need a: - Router
The link layer protocol used to get the IP address of a network node represented by a MAC address is called: - RARP
Each node of a network is identified at link layer by: - A MAC Address
Which of the following expressions is a valid IP address? - 200.200.200.200
We have the network configuration of the image and the routing table of the central node. The values of the fields Gateway and Interface of the second line will be:
- 198.65.1.1 and eth1
The layer that enables the connection to the phisycal medium is: - Link
The transport layer uses the concept of: - Port
We have the network configuration of the image and the routing table of the central node. The values of the fields Gateway and Interface of the third line will be:
- 10.10.0.1 and eth2
Frames are delimited by: - A fixed number of bits
The protocols of this layer use the underlying transport layer protocols to establish host-to-host connections: - Application
To connect two different subnetworks at link layer we need a: - Router
The protocol to transfer HTML web pages is:
- HTTP
The standard IEEE 802.3 refers to: - Ethernet networks with CSMA/CD
We have the network configuration of the image and the routing table of the central node. The values of the fields Gateway and Interface of the first line will be:
- 0.0.0.0 y eth0
The TCP protocol is: - A reliable protocol of the transport layer
The network layer that provides a communication free of errors between an origin and a destination is: - Transport
The standard IEEE 802.3 netwoks use: - Twisted pair cable
The layer that connects all the nodes connected directly to the same transmission medium is: - The physic layer
The network address of a class C network node with 132.54.7.3 IP address is: - 132.54.7.0
If we want to divide the 10.10.10.0 network into two identical subnetworks, the first valid IP of the second network will be:
- 10.10.10.129
The broadcast address of a class C network node with 132.54.17.13 IP address is: -132.54.17.255
The non reliable version of the TCP protocol is called: - UDP
A MAC address: - All are true
The actually used version of the IP protocol is: - TCP/IP
An IPv4 address can be dividen into: - Host Id and Subnetwork Id
Ports under the 1024: HTTP:80 DNS:53 POP3:110 SSH:22 SMTP:25 FTP:21
The protocol to get the IP address of a server name is: - DNS
The link layer protocol used to get the MAC address of a network node represented by an IP address is called: - ARP
The data link layer is divided into two sublayers: - No, it is not divided into two sublayers
IPv4 protocol use several bytes separated by the symbol: - Por un punto(.)
We have the address 80.15.12.35:75/web/index.html. 75 represents: - The port number in the network node
To configure a node in a network you have to indicate: - The network address and the gateway address
Routers use this to route the packets through the networks: - Routing table
If we want to divide the 10.10.10.0 network into two identical subnetworks, the subnetwork mask will be: - 255.255.255.0
IPv4 protocol use several groups of decimal numbers between: - 0..128
We have the address 80.15.12.35:75/web/index.html, index.html represents: - The port number in the network node
Internet layer protocols use packets based on: - TCP
El selector de memoria le indica a la memoria que queremos efectuar una operación de lectura en la posición 43Internet layer protocols use packets based on:
- 128 bits
The process of modifying IP address information in IP packet headers while in transit across a traffic routing device is called:
- Network Address Translation (NAT)
The protocols of the link layer are grouped in the family of standards: - IEEE 802
The transport layer identifies the clients and the server with: - An IP address and a port numberHow can you create a new user in Ubuntu?
Using the command useradd in the terminal
The default administrator user in Ubuntu is:
root
You can share a folder in Ubuntu going to:
File menu -> Sharing options -> Share this folder
What is the name of the default file browser in Linux?
Nautilus
The most popular repositories that are not officially supported by Ubuntu, but because they are maintained by the community they generally provide packages which are safe for use withyour Ubuntu computer are called:
Universe and Multiverse repositories
All the users in Ubuntu have a home directory in /home.
Yes
To install the apticron package, in a terminal enter:
sudo apt-get install apticron
How can you dismount and safely remove a removable drive?
With the appropriate option of the contextual menu
Linux file systems assign to each file or directory an identifier called:
Inode
To see the events of the system you have to go to:
System -> Administration -> System log (Log file viewer)
To indicate the value for the user's login directory when you are creating a new user, you have tu use the option:
There is no way to do it, the home directory name is always the same as the login of the user
Can you modify the TCP/IP configuration?
Yes, in System -> Preferences -> Network connections
The name of a shared folder in the network ...
It is always the same as the name of the folder in the computer
What does the expression [!123] mean?
It can be replaced by one character except the characters in brackets
Which is the directory where the CD-ROM units , USB memories or floppies are mounted in Ubuntu?
/media
The command apt-get has numerous advantages over other package management tools available in Ubuntu for server administrators. Some of these advantages are:
All are true
The inodes table stores:
All the information of the files and directories
Can you directly in Ubuntu make a compress file of the files and directories selected?
No, you need an special program for this
What kind of links exist in Ubuntu?
Two, hard and soft links
Ubuntu's package management system enables:
Installing, upgrading, configuring, and removing software
Which is the directory that contains the device management files?
R: /dev
Which command is a powerful commandline tool, which works with Ubuntu's Advanced Packaging Tool performing such functions as installation of new software packages, upgrade of existing software packages, updating of the package list index, and even upgrading the entire Ubuntu system?
R: aptget
The Ubuntu utility to make and restore backups:
R: All are true
The first column of information displayed in the package list in the top pane, when actually viewing packages lists the current state of the package, and uses the following key to describe the state of the package:
R:
Broken package B
Virtual package v
Installed package i
Package not installed, but package configuration remains on system c
Unpacked files, but package not yet configured u
Purged from system p
Which directory is opened when you open a terminal?
R: /home/user, where user is the login name of the active user
Which command is used to close the current user session?
R: exit
What is the result of launching Aptitude with no commandline options?
R: It will give you a menú-driven, text-based frondend to the Avvanced Packaging Tool system
What are the dependencies?
R:Dependencies are additional programs required bay one program in order to función properly
Which is the directory that contains the necessary files to boot the system?
R:/boot
Ubuntu's package management system does not enable:
R: To provide access to an organized base of over 35,000 software packages for your Ubuntu computer
Which file represents the standard error output?
/dev/stderr
To share folders in Ubuntu ...
You have to install samba
When you want to configure manually a network connection, you have to give these information:
All are true
The prompt of the root finishes with the symbol:
#
What is the Ubuntu command to change the password of a user?
passwd
Which of the next examples of popular uses for the apt-get utility is not correct?
sudo apt-get actualize
Which device is represented by the /dev/sda2 file?
The second partition of the first SATA or SCSI storage device
You can see the output of the long format list of files in the image. What is the meaning of the number in the second column?
(Hay una imagen que no puedo ver, pongo la que estaba puetso, pero no puedo comprobar que esta bien)
The number of links
Which Linux commands must we use to copy, move, delete and compare files in Ubuntu?
cp, mv, rm and cmp
To add a user to a group you have to go:
Using the command usermod
In which file is stored the configuration of the Advanced Packaging Tool system repositories?
Seleccione una respuesta.
/etc/apt/sources.list
To install the unattended-upgrades package you have to type in the terminal the command.
sudo apt-get install unattended-upgrades
Which device is represented by the /dev/sda file?
The first SATA or SCSI storage device
Which command returns working directory name?
pwd
Debian package files typically have the extension.
.deb
You can see the output of the long format list of files in the image. What is the meaning of data in the first column?
The type of the file and the permissions for the owner, the members of the group and the rest of users
APT::Periodic::Update-Package-Lists "1";
The above configuration updates the package list every day¿?
The command to directly enter into the home directory is
cd /
If you want to see the services that are running in the system:
You have to install the utility Service-Manager¿?
What is dpkg?
dpkg is a package manager for Debian-based systems
What is the best option to get all your files accessibles from any computer connected to Internet?
Use cloud storage.
What is the first problem in computer security?
People
A computer program that can replicate itself and spread from one computer to another is a:Seleccione una respuesta.
Virus
A small information sent by a website and stored on the user's browser so that the website can view the user's previous activity is called:
Cookie
A backup of latest changes since the last backup (any level) is called:
A differential backup
A type of data backup that preserves data, saving only the difference in the data since the last full backup is called:
An incremental backup;
What is the name of the windows command used to see the IP and the MAC addresses of a computer?
Ipconfig
In a network computer we do not have to consider for computer security purposes:
The operating system used
Which is the most secure encryption algorithm for Wi-Fi networks?
WPA-2
Where should I store my files in a shared computer?
In an external memory media
Which of the following is not a kind of malware?
Frontdoor
A firewall is not used for:
Automatic detection of attacks (creo que es esta pero no estoy muy segura)
A collection of updates, fixes, or enhancements to a software program delivered in the form of a single installable package is called:
A service pack or SP
A program that records the keys struck on a keyboard, typically in a covert manner so that the person using the keyboard is unaware that their actions are being monitored is a:
Keylogger
A method of bypassing normal authentication, securing illegal remote accessto a computer, obtaining access to plaintext, and so on, while attempting to remain undetected is:
Backdoor
What is the name of a program to detect intruders in your network?
Kismet
What problems can cause an intruder connected to your Wi-Fi network?
All are true
Which of the following items is not a kind of malware?
Cookies
Which of the following is not a commercial antivirus?
AVG
In a isolated computer we do not have to consider for computer security purposes:
The external media used in the computer
In order to maintain the data integrity you have to:
a. Create restauration points of the systemb. Create files with a password associated// esta es la correcta --- >c. All are trued. Create image files of the system
How many service packs have Windows XP and Windows 7
3
What is the name of the programs to prevent the connection of intruders to the system?
Firewalls
What is the best way to control who physically uses a shared computer?
Use login and password
For security reasons, the operating system and the rest of applications should beUpdated Which of the following is not a backup kind?
Partial
Which of the following is not a consideration for maintaining the data integrity?
We need a user with a password hard to find out
What is the name of the ubuntu command used to see the IP and the MAC addresses of a computer?
ifconfig
What is the name of the programs to intercept and log traffic passing over a digital network or part of a network?
Sniffers
When should you change the access password?
Periodically
What is the name of a program to detect the close hiden wireless networks?
inSSIDer
A temporary reduction in system performance, a system crash requiring manual restart, or a major crash with permanent loss of data is called:
Denial of service
Which of the following is not a cloud storage service?
Skydrive
What action is not necessary to be done in order to protect a Wi-Fi point access?
Configure an access to guests
A set of nearly identical messages sent to numerous recipients by email. These emails are unsolicited and sent in bulk.
Email spam
Malware:
A non-self-replicating type of malware which appears to perform a desirable function but instead drops a malicious payload. -> Trojan
The action of recording the keys struck on a keyboard, typically in a covert manner so that the person using the keyboard is unaware that their actions are being monitored -> keylogger
A software that obtains information about a person or organization without their knowledge and that may send such information to another entity without the consumer's consent. -> Spyware
A computer program that can replicate itself and spread from one computer to another. -> Virus
What is the name of a subnetwork used to add an additional layer of securityto a LAN? An external attacker only has access to equipment in it, rather than any other part of the network. The name is derived from the term "demilitarized zone", an area between nation states in which military action is not permitted.
DMZ
Typical used ports:
POP -> 110
SMTP -> 25
HTTP -> 80
HTTPS -> 443
IMAP -> 143
What is the name of an utility to check the system?
Conan
The software maintenance of a computer system consists of:
All are true
A collection of trees that share a common global catalog, directory schema, logical structure, and directory configuration, is called:Forest
To add a new printer to Windows 2008 Server, you have to go to:Start -> Server administrator -> Print services
To add a new function to Windows 2008 Server, you have to go to:Start -> Server administrator -> Add functions
What is SAMBA?A Linux Web Server
To configure the DNS in Ubuntu server, you have to:Type "dns 192.168.1.1" in the file /etc/network/interfaces (esta es la que marca en el examen)
Type "nameserver 192.168.1.1" in the file /etc/resolv.conf (esta es la que pienso que está bien)
What is the name of the protocol of the application level that enables users to manage the transfer of information on TCP/IP networks?FTP
What is the name of the file system that Windows 2008 Server uses?NTFS
A group policy can be established in:All are true
Which is the default GUI of Ubuntu Server?None
Can you execute in a Client computer an application installed in the Server?Yes, but you have to choose the application in the option remoteApp TS Administrator od the server
What is the name of the most popular DNS software for Linux?Bind
The objects of a domain can be grouped into:Domaines
The IP of the DNS of Google are:8.8.8.8 and 8.8.8.4
How can you change the name of the computer in the network in Windows 2008 Server?Start -> Right clic on My Computer -> Properties
If you want that a client receive an IP address automatically from the server, you have to:Configure it in the TCP/IP of the client
What is the command to change the password of the root user in Ubuntu?Sudo passwd root
When you change the network configuration in Ubuntu Server:You have to restart the service (/etc/init.d/networking restart)
What is the name of the service you have to install to Windows 2008 Server to enable the remote access to the server to administrate it through Remote Desktop?Terminal server
What is the name of the Web Server for Ubuntu Server?Apache
What kind of structure have DNS names?Llist
What is the name of the service you have to install in Windows 2008 Server to enable Linux computers to use the printers of this server?Print$
What is the name of the Web Server for Ubuntu Server?Apache
What kind of structure have DNS names?llist
If you want to configure SAMBA you have to modify the file:/etc/samba/smb.conf
What do you have to do to use the first time the root user in Ubuntu Server?Introduce the password for root (sudo passwd root) and change to the root user (su root)
A collection of several domains in a contiguous namespace, linked in a transitive trust hierarchy, is called:Tree
What is the network FQDN name of a computer called PC01 in the domain called daw1.es?daw1.es/PC01
The last symbol of the prompt for root is:#
The network name given to the computer in the operating system installation is called:DNS
What is the name of the component of Windows 2008 Server to manage web pages?IIS (Internet Information Server)
When you install AD in a Windows 2008 Server it becomes:Directory controller
The Ubuntu Server needs two partitions to run:Linux operating systems need a minimum of one partition: one for the OS itself (and data files) and optionally one for a swap area (to be used as an extension for RAM memory) if preferred over a swap file. (one for / and another for swap)
The Ubuntu Server must be installed in a partition with the following characteristics:Type: Primary File system: physical volume for RAID mount: / - the root file system
If you want to create OU, users or groups in Windows 2008 Server, you have to go to:Start -> Control pannel -> Users and computers of AD
What is the name of the last version of Windows Server?2012
The main service to resolve domain names in TCP/IP is called:DNS
The physical directory used by the IIS to store the web pages is:C:\inetpub\wwwroot\
What is LAMP?A Linux Web Server
What kind of relationship may be established between two domains?Trust
How can you test if the DNS configuration is correct?Executing several ping with the names introduced in the /etc/hosts file
What file system uses the swapping partition of Ubuntu Server?None
A DNS server manages the database of couples:IP v4 - IP v6
Which of the following is not an edition of Windows 2008 Server?Professional
What is the mount point of the swapping partition of Ubuntu Server?/boot
In the DNS service, an inverse search zone is:
Returns the name of the computer identified by an IP
The sets of configurations that control what users can and cannot do on a computer domain are called:Group Policy Object (GPO)
What is the name of the Ubuntu Server file where you can see, insert or modify the couple IP-Name for the DNS server?/etc/hosts
After installing IIS in Windows 2008 Server, you have to modify a file to add the couple IP (192.168.1.2) - Web name (www.clase.es). What is the name of this file?Hosts
What is the name of the service you have to install in Windows 2008 Server to assign automatically an IP of the configured range to each computer that requires it?DHCP
Actually the more common network architecture is:Client – Server
The hardware of the server computer:Should be better than the desktop computers
The path where the profiles of the users are stored is:C:\Documents and settings\Profiles
P-------- The command to execute commands as superuser is:R: su
p-------- Which is not an advantage of GNU/Linux systems?R: Close source
P-------- Which of the following is not a characteristic of Ubuntu systems?R: They are a simplest version of Debian
P-------- The Ubuntu elements with the same utility that Windows toolbarsare:R: Panels
P-------- Linux repositories and official servers are controlled by:R: Expert programmers called commiters
P-------- You can add an applet to a panel in Ubuntu:R: System -> Administration -> Applets
P-------- LINUX word comes from:R: Its creator and Unix
P-------- The default graphical interface of Ubuntu is:R: Gnome
P-------- Which item is not present in the top panel?R: Documents menu
P-------- Which command is used to show you the manual of other commands?R: Man
P-------- Which symbol stands for your home directory?R: c..
P-------- To create a new panel you have to do:R: System -> Preferences -> Panels
P-------- The redirection operator to add information to a file is:R: >
P-------- The operating system that Andrew S. Tanenbaum built in 1987 foracademic purpouses was called:R: MINIX
P-------- Which key lets you scrolls through the commands you've entered previously?R: Up Arrow
P-------- The application to see the devices installed in the system is:R: Device manager
P-------- Software is free software if people who receive a copy of the software have four freedoms. Which of the following is not one of this freedoms?R: The freedom to run the program for any purpose
P-------- You can change the name of the machine:R: Applications -> Accessories -> Terminal -> sudo gedit /etc/hostname
P-------- The repositories are divided in these sections:R: main, restricted, universe and multiverse
P-------- When the screensaver appears in Ubuntu:R: You always have to enter the password to access the machine
P-------- Which command will assign a password for the newuser account?R: passwd newuser
P-------- You can change the language of the Ubuntu interface:R: System -> Administration -> Language support
P-------- The Ubuntu element with the same utility that the Control Panel icon in Windows is:R: System
P-------- You can install new programs in Ubuntu with:R: Synaptic package manager
P-------- Which command will create a new general user called "newuser" on your system?R: adduser newuser
P-------- You can add the Computer, Home, Network and Trash icons to the desktop:R: Click [Alt]+[F2] -> Type gconf-editor -> Click Run button -> Choose
apps, nautilis, desktop -> Check the corresponding boxes
P-------- You can change the way you begin a session:R: System -> Preferences -> Enter session
P-------- To create a launcher to an application in the desktop, we have to do:R: Click on the application and drag and drop it on the desktop
P-------- You can configure the keyboard:R: System -> Control panel -> Keyborad
P-------- The administrator user (superuser) in Ubuntu is called:R: root
P-------- The Unix-like computer operating system based on a microkernel architecture created by Andrew S. Tanenbaum for educational purposes thatinspired the creation of the Linux kernel was:R: MINIX
P-------- The format of packages usually used in systems based on Red Hatand Debian are:R: DEB and RPM
P-------- The interface between the user and the system is called:R: Shell
P-------- The Ubuntu menu with the same utility that the All programs menu in Windows is:R: Applications
P-------- Which command displays the amount of free and used memory in the system?R: Free
P-------- The process with which the user uses the system through its terminal is called:R: Shell
P-------- An example of Linux distribution promoted by a government:R: Lliurex
P-------- The programs organized and ready to be installed are called:R: packages
P-------- Ubuntu is a computer __________ based on the __________ Linux distributionR: Operating system, Debian
P-------- Ubuntu is distributed as:R: An installation USB memory(?)
P-------- The Ubuntu versions with a maintenance period of three years for the desktop, and five years on servers are called:R: LTS (Long Term Support)
P-------- What is the meaning of GNU?R: GNU's Not Unix
P-------- The Ubuntu elements with the same utility that Windows shortcuts are:R: Toolbar
P-------- Which option of the mouse can not be configured in Ubuntu?R:Â Cursor blinking
P-------- Examples of shells:R: csh and ksh
P-------- Which of the next statements is false?R: A software with its source code may be not free software, it must comply the four freedoms
P-------- You can change the theme of Ubuntu:R: System -> Preferences -> Apperance -> Theme
P-------- The operator for the redirection of the standard input is:R: <
P-------- An example of Linux distribution promoted by a community:R: Lliurex
P-------- Which command will allow you to know in which directory you're located?R: dirWhen changes a process its status from Blocked to Stopped?An event occurs and the process is not longer blockedWhat is the name of the memory address of an interrupt handler?Interrupt service routineThe CPU executes a program that controls the I/O operations in the I/O model:All are falseWe have:CPU scheduling algorithm: PrioritiesProcess arrival time: A=0, B=1, C=2, D=3.Process CPU time required: A=8, B=4, C=9, D=5.Process priority: A=2, B=1, C=4, D=2 (Priority of 4 > Priority of 1)
10.33When changes a process its status from In execution to Stopped?The operating system takes out the process from the CPUbecause it has been in execution too much timeA logical partition must be always inside:An extended partitionWhat happens when a process needs a condition that the system can not offerimmediately?BlockedWe have:RR q=3 CPU scheduling algorithm.Process arrival time: A=0, B=1, C=2 and D=3.Process CPU time required: A=8, B=4, C=9 and D=5.
13.5A signal interrupts the execution of the CPU to inform it that an event has occurred in the I/O model:I/O contrlled by interruptionsA chip controls the I/O operations while the CPU executer other processes in the I/Omodel:I/O controlled by DMA
What is the name of the memory management method where the process isdivided in parts of the same size?PagingWindows 7 is an operating system:Multiuser, multitask, multiprocessor and for desktop computers.What is the name of the element that says which process uses the CPU and forhow many time?The schedulerWhen a process is stopped waiting to be executed, it is in a status:StoppedA program in execution is called:ProcessOperating systems can work in two modes:Kernel and userWe have the directories tree shown in the image. The work directory is ee51vn.Which is the absolute path of the file report.doc?/home/its/ug1/ee51vn/report.docA process gives a logical address 2453. The system uses pages of 1024 words.May this logical address be translated to the physical address 9322?No, it is too greatThe main functions of the operating systems are:Process, Memory, files and I/O managementWhen changes a process its status from Stopped to In execution?The operating system choose it to use the CPUA process can not be in the following status:IdleWhen does a context change occur?When the scheduler changes the process in executionWhich of the following terms is not an algorithm used to choose the process thatis going to use the CPU?LIFOWe have:Multilevel queue CPU scheduling algorithm.A and C are batch process, B and D are interactive process.Interactive processes have greater priority than batch processes.RR Q=2 scheduling algorithm for interactive processes.FCFS scheduling algorithm for batch processes.Process arrival time: A=0, B=2, C=4 and D=5.Process CPU time required: A=5, B=5, C=5 and D=7.7.25
We have:SJF CPU scheduling algorithm.Process arrival time: A=0, B=1, C=2 and D=3.Process CPU time required: A=8, B=4, C=9 and D=5.7.75Status process diagram:
4:waiting2:ready3:running5:terminated1:newThe applications use the services that offers the operating system with:System callsWhich of the following statements about virtual memory is false?The virtual memory does not need any protectionThe memory that solves the problems of RAM memory (limited size and volatility)isCache memoryIn what operating systems can one processor work with several processes "at thesame time"?Shared time systemsWe have the directories tree shown in the image. The work directory is tmp.Which is the relative path of the file report.doc?../home/its/ug1/ee51vn/report.docWhen changes a process its status from In execution to Blocked?The process can not go on using the CPU until an eventoccursA technical that uses a little memory to store a copy of the more frequently useddata is called:CachingWe have:FCFS CPU scheduling algorithm.Process arrival time: A=0, B=1, C=2 and D=3.Process CPU time required: A=1, B=100, C=1 and D=100.The waiting time average is:49.5The information of the process of the system is stored in:The process tableWhich of the following statements about process is false?There is an image stored in secondary memory for eachprocessWhich is not a kind of partition?PhysicalData is stored in the secondary storage as:
FilesWhat happens when two process are blocked waiting for resources that are occupied by the other process?A deadblock
We have a paged virtual memory system, with 4 frames of memory, initially filledwith the pages A, B, C and D. We have the following sequence of pagereferences: C, A, D, B, E, B, A, B, C and D. How many page faults will occur withthe optimal page replacement algorithm?0What kinds of partitions organization do hard disks support?MBR or GPTWe have:FCFS CPU scheduling algorithm.Process arrival time: A=0, B=1, C=2 and D=3.Process CPU time required: A=100, B=100, C=1 and D=1.The waiting time average is:123.75A process can be divided in several:ThreadsThe scheduler uses the following structures:All are trueA completely isolated guest operating system installation within a normal hostoperating system is:A virtual machineWe have a paged virtual memory system, with 4 frames of memory, initially filledwith the pages A, B, C and D. We have the following sequence of pagereferences: C, A, D, B, E, B, A, B, C and D. How many page faults will occur withthe FIFO page replacement algorithm?0In communication networks, what is the name of a connection point, either a redistribution point or a communication endpoint (some terminal equipment)?Node
Which of the following addresses is a valid physical address
192.168.105.1
An organization that share devices, saves
All are true
What is the name of the design of a communications network?
Network architecture
How many layers have the TCP/IP architecture?
Four: Application, Transport, Internet and Network Access
What is the name of the model of network architecture implemented in Internet and in most of the networks?
TCP/IP
Each layer of a network architecture interacts with the neigbourh layers through:
Interface
In which of the TCP/IP layer are defined the protocols TCP, UDPand RTP?
Application
In which of the TCP/IP layer are defined the protocols IP, ICMP, ARP and RARP?
Network interface
Which was the world's first operational packet switching network and the progenitor of what was to become the global Internet?
ARPANET
In data communication, a physical network node may either bea __________ (modem, hub, bridge or switch) or a __________ (a
digital telephone handset, a printer or a host computer.
LAN and WAN
The type of network topology in which a central 'root' node (the top level of the hierarchy) is connected to one or more other nodes that are one level lower in the hierarchy (i.e., the second level) with a point-to-point link between each of the second level nodes and the top level central 'root' node.
Tree network topology
In which of the TCP/IP layer are defined the protocols Ethernet, Token Ring, FDDI, X.25, Frame Relay, RS-232 and v.35?
Transport
Telephones use this kind of cable and connectors:
Twisted pair cable and RJ-45 connectors
The OSI model is a way of sub-dividing a communications system into smaller parts called:
Layers
Which of the TCP/IP layers provides communication session management between host computers. Defines the level of service and status of the connection used when transporting data?
Network interface
Which of the following addresses is a valid logical address:
192.168.105.1
It is an electronic device that receives a signal, cleans it of unnecessary noise, regenerates it, and retransmits it at a higher power level, or to the other side of an obstruction, so that the signal can cover longer distances without degradation.
Network interface cards
It is a device that forwards and filters OSI layer 2 datagrams (chunks of data communication) between ports (connected cables) based on the MAC addresses in the packets. It is distinct from a hub in that it only forwards the frames to the ports involved in the communication rather than all ports connected. It breaks the collision domain but represents itself as a broadcast domain. They make forwarding decisions of frames on the basis of MAC addresses. It normally has numerous ports
Bridge
A repeater with multiple ports
Repeater
It is an internetworking device that forwards packets between networks by processing information found in the datagram or packet (Internet protocol information from Layer 3 of the OSI Model). In many situations, this information is processed in conjunction with the routing table (also known as forwarding table). They use routing tables to determine what interface to forward packets (this can include the "null" also known as the "black hole" interface because data can go into it, however, nofurther processing is done for said data).
Hub
It is a piece of computer hardware designed to allow computers to physically access a networking medium. It provides a low-level addressing system through the use of
MAC addresses.
Router
It connects multiple network segments at the data link layer (layer 2) of the OSI model. They broadcast to all ports except the port on which the broadcast was received. However, they do not promiscuously copy traffic to all ports, as hubs do, but learn which MAC addresses are reachable through specific ports. Once it associates a port and an address, it will send traffic for that address to that port only.
Switch
10BASE-T networks use:
Coaxial cable
The physical and the logical addresses of a NIC are called respectively:
MAC and IP
Wireless transmission:
These waves travel in straight lines, so the sender and the receiver must be carefully aligned
Microwave
Directional electromagnetic waves incapable of pass through solid objects that are suitable for short-distance transmissions
Infrared
They can be used to communicate two neighboring buildings installing in each of them a laser emitter and a photodetector.
Ligth waves
Wi-Fi, Home RF or Bluetooth
Radio waves
In which of the TCP/IP layer are defined the protocols HTTP, Telnet, FTP, TFTP, SNMP, DNS, SMTP and X Windows?
Application
Internet is a:
LAN
To connect a LAN to Internet we use:
Modem
Ethernet networks have a data rate: 10 Gbps
They are devices that perform the same function as a wiring hub, ie centralize network connections. This device operates on a wireless network, and all the equipment connections it has in its range end up in it.
Ad-hoc
Optical fiber cables can be: Single or couplesSingle-mode or mono-mode fiberAll are true <------ Think or thick
A computer network can beA server or a host
A 10BASE2 cable:
It is also caller thin ethernetIt uses BCN connectorIt supports 10 MgpsAll are true <--------
The geometric form of the distribution of nodes and cables in a network is called:
Topology
Computers can be interconnected:
Only with network cards or wireless access points
An interconnection system between devices that allows to share informations and resources is a:
Computer network
A set of networks, using the Internet Protocol and IP-based tools such as web browsers and file transfer applications, that is under the control of a single administrative entity is a:
Intranet
Wireless technologies:
They use several radio communications technologies. The systems are divided to different geographic areas. Each area has a low-power transmitter or radio relay antenna device to relay calls from one area to the next area.
Cellular and Pcs systems
They use microwave radio as their telecommunications medium which are not deflected by the Earth's atmosphere. The satellites are stationed in space, typically 35,400 km (22,000 mi) (for geosynchronous satellites) above the equator. These Earth-orbiting systems arecapable of receiving and relaying voice, data, and TV signals.
Communications satellites
They can transmit signals between devices within small distances of typically no more than 10 meters. In mostcases, line-of-sight propagation is used, which limits the physical positioning of communicating devices.
Infrared communications
They use a high-frequency radio Wireless LANs
technology similar to digital cellular and a low-frequency radio technology. They use spread spectrum technology to enablecommunication between multiple devicesin a limited area. An example of open-standards wireless radio-wave technology is IEEE 802.11.
They use Earth-based transmitter and receiver. The equipment looks similar to satellite dishes. They use low-gigahertz range, which limits all communications to line-of-sight.
Terrestrial microwave
A layer is a collection of similar __________ that provide __________ to the layer above it and receives __________ from the layer below it.
functions, services, services
What is the name of the model of network architecture widely studied in networking theory?
TPC
A __________ is a collection of __________ and other hardware interconnected by communication channels that allow sharing of resources and information.
network, computers
Components of a communication system:
Device that generates the message Transmmiter
Destination device of the message Reciever
Physical medium used to transfer the information
Channel
Contains the information that we want to send
Message
Set of rules that govern the data transmission
Protocol
It is a device that converts digital signals from the computer to analog signals forthe phone line (modulation), sends them to another computer, and when it receives them re-convert the signals from analog to digital (demodulation).Choose one answer.
Digital modem
Kinds of twisted pair cable: They have a conductive shield for each pair of cables and one global. They have the best noise immunity.
FTP or Fully Shielded Twisted Pair
They are the most simple cables. They have no conductor shield. They are very flexible and very sensible to interferences.
UTP or Unshieled Twisted Pair
Each pair of cables is surrounded with a conductive shield, which is connected to the different earth connections. They have a high noise immunity
S/STP or Screened Shielded Twisted Pair
They have a global twisted conductive shield. STP or Shielded Twisted Pair
Which of the TCP/IP layers specifies details of how data is physically sent through the network, including how bits are electrically signaled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted-pair copper wire?
Transport
Which of the TCP/IP layers defines TCP/IP application protocols and how host programs interface with transport layer services to use the network?
Internet
